Electronic Journal of Statistics

Expectiles for subordinated Gaussian processes with applications

Jean-François Coeurjolly and Hedi Kortas

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In this paper, in order to deal with data rounding issues, we introduce a new class of estimators of the Hurst exponent of the fractional Brownian motion (fBm) process. These estimators are based on sample expectiles of discrete variations of a sample path of the fBm process. So as to derive the statistical properties of the proposed estimators, we establish asymptotic results for sample expectiles of subordinated stationary Gaussian processes with unit variance and correlation function satisfying ρ(i)κ|i|α (κℝ) with α>0. Via a simulation study, we demonstrate the relevance of the expectile-based estimation method and show that the suggested estimators are more robust to data rounding than their sample quantile-based counterparts.

Article information

Electron. J. Statist., Volume 6 (2012), 303-322.

First available in Project Euclid: 8 March 2012

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 60G18: Self-similar processes
Secondary: 62G30: Order statistics; empirical distribution functions

Expectiles robustness local shift sensitivity subordinated Gaussian process fractional Brownian motion


Coeurjolly, Jean-François; Kortas, Hedi. Expectiles for subordinated Gaussian processes with applications. Electron. J. Statist. 6 (2012), 303--322. doi:10.1214/12-EJS674. https://projecteuclid.org/euclid.ejs/1331216628

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